Harley-Davidson Tri Glide Ultra (114 cui) – FLHTCUTG/23 Specs: Oil Capacity & Tire Pressure

At MotoSpecsLab, we evaluate machinery based on engineering integrity and purpose-built design. A little-known fact regarding the Harley-Davidson Tri Glide Ultra (FLHTCUTG) is that unlike many aftermarket trike conversions, the Tri Glide was engineered from the ground up by Harley-Davidson with a unique frame and chassis designed specifically to handle the lateral forces of a three-wheeled configuration. This dedicated geometry prevents the ‘flex’ often found in bolt-on kits, providing a level of stability and cargo capacity (6.8 cubic feet) that defines the modern American touring trike.

Engineering & Power Delivery

The heart of the FLHTCUTG/23 is the Milwaukee-Eight 114 V-Twin engine. This 1,868cc powerhouse utilizes precision oil/air cooling to manage thermal loads, particularly important on a heavy three-wheeled platform. With 118 ft-lb of torque peaking at 3,000 RPM, the power delivery is optimized for low-end grunt, allowing for effortless highway merging even when the 125-pound capacity trunk and King Tour-Pak are fully loaded.

Maintenance Guide & Lubrication

For the 114 cubic inch engine, maintaining oil viscosity is critical for hydraulic lifter performance and cooling. MotoSpecsLab recommends 20W-50 H-D 360 for standard climates or Screamin’ Eagle Syn3 for high-temperature environments. The system requires 3.8 liters (approx. 4.0 quarts) for a full filter change.

• Primary Chaincase: Inspect every 5,000 miles; use dedicated Formula+ lubricant.
• Transmission: 6-speed Cruise Drive requires specific gear lubricant to ensure smooth engagement of the electric reverse gear.
• Spark Plugs: Utilize 6R10 plugs gapped to specification to ensure complete combustion in the 4-valve heads.

Chassis & Tire Management

The Tri Glide Ultra utilizes a unique tire setup. The front 19-inch wheel requires 36 psi (2.5 bar) to maintain steering precision. The rear automotive-style tires require a significantly lower 26 psi (1.8 bar). Running the rears at higher pressures will result in a harsh ride and reduced contact patch, compromising the Reflex Linked Brembo Braking system with ABS.

Electrical System

The FLHTCUTG/23 utilizes the high-output 66000041 battery. Given the electrical load of the Boom!™ Box GTS infotainment system and the electric reverse motor, maintaining the battery on a tender during storage is mandatory to prevent premature failure of the charging system’s stator.